Monday, May 20, 2013 CNN.com - Top Stories: Watch tornado form over Oklahoma CNN.com - Top Stories CNN.com delivers up-to-the-minute news and information on the latest top stories, weather, entertainment, politics and more. Watch tornado form over Oklahoma May 20th 2013, 23:40 The National Weather Service declares a tornado emergency as a massive storm hits Oklahoma. You are receiving this email because you subscribed to this feed at blogtrottr.com. If you no longer wish to receive these emails, you can unsubscribe from this feed, or manage all your subscriptions Tweet